After a 14-year saga involving a bargain-bin purchase from Ukraine, painstaking renovations and much obfuscation, in the summer of 2012 China commissioned its first aircraft carrier, the second-hand Liaoning.

Lots of people in the U.S. and its allies freaked out, although the flattop itself is of limited utility. One small carrier is really just a target for Americaâ€™s warplanes and submarines.

More worrying for Chinaâ€™s maritime rivals including America was Beijingâ€™s vow to build at least two more carriers. Bigger ones. With better systems. And maybe even stealth planes to fly off them.

Now we might have glimpsed the earliest evidence of the first of these homegrown flattops, in hazy photos from northern Chinaâ€™s Dalian shipyard leaked onlineâ€”presumably by the legions of government-sponsored Internet users who function as Beijingâ€™s street-level propagandists.

The photos seems to depict one of the new carrierâ€™s blocksâ€Šâ€”â€Šthat is, a section of the hull that later will be welded to other sections to produce the entire vessel.

Whatâ€™s most compelling is the divot in the deck, identified by the red square on the photo above. Thatâ€™s apparently a trench for a steam-powered airplane catapult.

Thatâ€™s a big deal because like Russiaâ€™s sole carrier, Liaoning doesnâ€™t have a catapult, so it can launch only lightly-loaded warplanes. The Russian and Chinese Flanker carrier jets fly from their flattops with minimal fuel and weaponry, putting them at a disadvantage against American and French carrier fighters that are boosted fully loaded by their shipsâ€™ catapults.

With this apparent evidence of a new carrier, Chinaâ€™s future naval plan is becoming clearer. The new flattop could carry the latest warplanes, possibly including a sea-based version of the Chinese J-31 stealth fighter prototype, unveiled last fall. The J-31 features the heavy-duty twin nose wheels that are typical of flattop-based planes.

Itâ€™s not clear when the home-made carrier might enter service. American flattops take nearly a decade to build. Chinaâ€™s could take longer, especially given Liaoningâ€™s tortured development (it was originally launched by the Soviets in 1988).

If China aims to challenge the U.S. Navy at sea, a big fleet of carriers is a good startâ€Šâ€”â€Šalthough submarines would be a cheaper and more dangerous option. For now, America has a huge aviation advantage, with 10 carriers in service, powerful air wings and 100 years of flattop experience.

But if these snapshots are any indication, China could catch up soon in the at-sea arms race.